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<article xmlns:xlink="http://www.w3.org/1999/xlink">
  <front>
    <journal-meta />
    <article-meta>
      <title-group>
        <article-title>A Taxonomy of Enterprise Search</article-title>
      </title-group>
      <contrib-group>
        <contrib contrib-type="author">
          <string-name>Tony Russell-Rose</string-name>
          <xref ref-type="aff" rid="aff1">1</xref>
        </contrib>
        <contrib contrib-type="author">
          <string-name>Joe Lamantia</string-name>
          <email>jlamantia@endeca.com</email>
          <xref ref-type="aff" rid="aff0">0</xref>
        </contrib>
        <contrib contrib-type="author">
          <string-name>Mark Burrell</string-name>
          <email>mburrell@endeca.com</email>
          <xref ref-type="aff" rid="aff0">0</xref>
        </contrib>
        <aff id="aff0">
          <label>0</label>
          <institution>Endeca</institution>
          ,
          <addr-line>101 Main St., Cambridge, USA, +1 617 674 6000</addr-line>
        </aff>
        <aff id="aff1">
          <label>1</label>
          <institution>UXLabs Ltd.</institution>
          ,
          <addr-line>London, UK, +44 7779 936191</addr-line>
        </aff>
      </contrib-group>
      <abstract>
        <p>Classic IR (information retrieval) is predicated on the notion of users searching for information in order to satisfy a particular “information need”. However, it is now accepted that much of what we recognize as search behaviour is often not informational per se. For example, Broder (2002) has shown that the need underlying a given web search could in fact be navigational (e.g. to find a particular site or known item) or transactional (e.g. to find a sites through which the user can transact, e.g. through online shopping, social media, etc.). Similarly, Rose &amp; Levinson (2004) have identified consumption of online resources as a further category of search behaviour and query intent. In this paper, we extend this work to the enterprise context, examining the needs and behaviours of individuals across a range of search and discovery scenarios within various types of enterprise. We present an initial taxonomy of “discovery modes”, and discuss some initial implications for the design of more effective search and discovery platforms and tools.</p>
      </abstract>
      <kwd-group>
        <kwd>eol&gt;Enterprise search</kwd>
        <kwd>information seeking</kwd>
        <kwd>user behaviour</kwd>
        <kwd>knowledge workers</kwd>
        <kwd>search modes</kwd>
        <kwd>information discovery</kwd>
        <kwd>user experience design</kwd>
      </kwd-group>
    </article-meta>
  </front>
  <body>
    <sec id="sec-1">
      <title>1. INTRODUCTION</title>
      <p>
        To design better search and discovery experiences we must
understand the complexities of the human-information seeking
process. Numerous theoretical frameworks have been proposed to
characterize this complex process, notably the standard model
        <xref ref-type="bibr" rid="ref13">(Sutcliffe &amp; Ennis 1998)</xref>
        , the cognitive model (Norman 1998) and
the dynamic model
        <xref ref-type="bibr" rid="ref2">(Bates, 1989)</xref>
        . In addition, others have
investigated search as a strategic process, examining the various
Copyright © 2011 for the individual papers by the papers' authors.
Copying permitted only for private and academic purposes. This volume
is published and copyrighted by the editors of euroHCIR2011.
problem solving strategies and tactics that information seekers
employ over extended periods of time
        <xref ref-type="bibr" rid="ref4">(e.g. Kuhlthau, 1991)</xref>
        .
In this paper, we examine the needs and behaviours of varied
individuals across a range of search and discovery scenarios
within various types of enterprise. These are based on an analysis
of the scenarios derived from numerous engagements involving
the development of search and business intelligence solutions
utilizing the Endeca Latitude software platform. In so doing, we
extend the classic IR concept of information-seeking to a broader
notion of discovery-oriented problem solving, accommodating the
much wider range of behaviours required to fulfil the typical goals
and objectives of enterprise knowledge workers.
      </p>
      <p>
        Our approach to enterprise discovery is an activity-centred model
inspired by Don Norman’s Activity Centred Design, which
“organizes according to usage” whereas “...traditional human
centred design organizes according to topic, in isolation, outside
the context of real, everyday use.”
        <xref ref-type="bibr" rid="ref9">(Norman 2006)</xref>
        . This approach
is an extension of previous activity-centred modelling efforts
which focused on a “captur[ing] a systematic and holistic view of
what users need to accomplish when undertaking information
retrieval tasks more complex than searching”
        <xref ref-type="bibr" rid="ref5">(Lamantia 2006)</xref>
        ,
employing Grounded Theory to provide methodological structure
        <xref ref-type="bibr" rid="ref6">(Glaser 1967)</xref>
        .
      </p>
      <p>In this context, we present an alternative model focused on
information discovery rather than information seeking per se,
which has at its core an initial taxonomy of the “modes of
discovery” that knowledge workers employ to satisfy their
information search and discovery goals. We then discuss some
initial implications of this model for the design of more effective
search and discovery platforms and tools.</p>
    </sec>
    <sec id="sec-2">
      <title>2. INFORMATION RETRIEVAL MODELS</title>
      <p>
        The classic model of IR assumes an interaction cycle consisting of
four main activities: the identification an information need, the
specification of an appropriate query, the examination of retrieval
results, and reformulation (where necessary) of the original query.
This cycle is then repeated until a suitable result set is found
        <xref ref-type="bibr" rid="ref12">(Salton 1989)</xref>
        .
      </p>
      <p>In both the above models, the user’s information need is assumed
to be static. However, it is now acknowledged that information
seekers’ needs often change as they interact with a search system.
In recognition of this, alternative models of information seeking
have been proposed. For example, Bates (1989) proposed the
dynamic “berry-picking” model of information seeking, in which
the information need (and consequently the query) changes
throughout the search process This model also recognises that
information needs are not satisfied by a single, final result set, but
by the aggregation of results, insights and interactions along the
way.</p>
      <p>
        Bates’ work is particularly interesting as it explores the
connections between the dynamic model and the search strategies
and tactics that professional information-seekers employ. In
particular, Bates identifies a set of 29 individual tactics, organised
into four broad categories
        <xref ref-type="bibr" rid="ref1">(Bates, 1979)</xref>
        . Likewise, O’Day &amp;
Jeffries (1993) examined the use of information search results by
clients of professional information intermediaries and identified
three distinct “search modes” or major categories of search
behaviour: (1) Monitoring a known topic or set of variables over
time; (2) Following a specific plan for information gathering; (3)
Exploring a topic in an undirected fashion.
      </p>
      <p>O’Day and Jeffries also observed that a given search would often
evolve over time into a series of interconnected searches,
delimited by certain triggers and stop conditions that indicate the
transitions between modes or individual searches executed as part
of an overall enquiry or scenario. Moreover, O’Day &amp; Jeffries
also attempted to characterise the analysis techniques employed
by the clients in interpreting the search results, identifying the
following six primary categories: (1) Looking for trends or
correlations; (2) Making comparisons; (3) Experimenting with
different aggregations/scaling; (4) Identifying critical subsets; (5)
Making assessments; (6) Interpreting data to find meaning.
More recent investigations into the relationship between
information needs and search activities include that of
Marchionini (2005), who identifies three major categories of
search activity, namely “Lookup”, “Learn” and “Investigate”.</p>
    </sec>
    <sec id="sec-3">
      <title>3. A TAXONOMY OF ENTERPRISE</title>
    </sec>
    <sec id="sec-4">
      <title>SEACH AND DISCOVERY</title>
      <p>The primary source of data in this study is a set of user scenarios
captured during numerous engagements involving the
development of search and business intelligence solutions
utilizing the Endeca Latitude software platform. These scenarios
take the form of a simple narrative that illustrates the user’s end
goal and the primary task or action they take to complete it,
followed by a brief description of their job function or role, for
example:
•
•
“I need to understand a portfolio’s exposures to assess
portfolio-level investment mix” (Portfolio Manager)
“I need to understand the quality performance of a part
and module set in manufacturing and the field so that I
can determine if I should replace that part”
(Engineering)
These scenarios were manually analyzed to identify themes or
modes that appeared consistently throughout the set. For example,
in each of the scenarios above there is an articulation of the need
to develop an understanding or comprehension of some aspect of
the data, implying that “comprehending” may constitute one such
discovery mode. Inevitably, this analysis process was somewhat
iterative and subjective, echoing the observations made by Bates
(1979) in the identification of her search tactics: “While our goal
over the long term may be a parsimonious few, highly effective
tactics, our goal in the short term should be to uncover as many
as we can, as being of potential assistance. Then we can test the
tactics and select the good ones. If we go for closure too soon,
i.e., seek that parsimonious few prematurely, then we may miss
some valuable tactics.”
There are however some guiding principles that we can apply to
facilitate convergence on a stable set. For example, an ideal set of
modes would exhibit properties such as: Consistency (they
represent approximately the same level of abstraction);
Orthogonality (they operate independently to each other); and
Comprehensiveness (they address the full range of discovery
scenarios).</p>
      <p>The initial set of discovery modes to emerge from this analysis
consists of a set of nine, arranged into three top-level categories
consistent with those of Marchionini (2005). The nine modes are
as follows, each shown with a brief definition:</p>
      <sec id="sec-4-1">
        <title>1. Lookup</title>
      </sec>
      <sec id="sec-4-2">
        <title>2. Learn</title>
        <p>1a. Locating: To find a specific (possibly known) item; 1b.
Verifying: To confirm or substantiate that an item or set of items
meets some specific criterion; 1c. Monitoring: To maintain
awareness of the status of an item or data set for purposes of
management or control.
2a. Comparing: To examine two or more items to identify
similarities &amp; differences; 2b. Comprehending: To generate
insight by understanding the nature or meaning of an item or data
set; 2c. Exploring: To proactively investigate or examine an item
or data set for the purpose of serendipitous knowledge discovery.</p>
      </sec>
      <sec id="sec-4-3">
        <title>3. Investigate</title>
        <p>3a. Analyzing: To critically examine the detail of an item or data
set to identify patterns &amp; relationships; 3b. Evaluating: To use
judgment to determine the significance or value of an item or data
set with respect to a specific benchmark or model; Synthesizing:
To generate or communicate insight by integrating diverse inputs
to create a novel artefact or composite view.</p>
        <p>Evidently, the output of this process has been optimized for the
current data set and in that respect represents an initial
interpretation that will need to evolve further. For example,
“monitoring” may appear to be a lookup activity when considered
in the context of a simple alert message, but when viewed as a
strategic activity performed by an executive in the context of an
organisational dashboard, a much greater degree of interaction
and complexity is implied. Conversely, “exploring” is a concept
whose level of abstraction may prove somewhat higher than the
others, thus breaking the consistency principle suggested above.
However, the true value of the modes will be realised not by their
conceptual purity or elegance but by their utility as a design
resource. In this respect, they should be judged by the extent to
which they facilitate the design process in capturing important
characteristics common to enterprise search and discovery
experiences, whilst flexibly accommodating arbitrary variations in
domain, information resources, etc.</p>
      </sec>
    </sec>
    <sec id="sec-5">
      <title>4. MODE SEQUENCES AND PATTERNS</title>
      <p>
        A further interesting observation arising from the above analysis
is that the mapping between scenarios and modes is not one-to–
one. Instead, some scenarios are seen to involve a number of
modes, sometimes with a primary or dominant mode, and often
with an implied linear sequence. Moreover, certain sequences of
modes tend to re-occur more frequently than others, forming
specific “mode chains” or patterns, analogous to higher-level
syntactic units. These patterns provide a framework for
understanding the transitions between modes (echoing the triggers
identified by O’Day &amp; Jeffries), and allude to the existence of
natural seams that can be used be used to provide further insight
into information enterprise search and discovery behaviour.
These mode chains echo the above-mentioned efforts to create
goal-based information retrieval models, which yielded modes
and a set of broadly applicable “information retrieval patterns that
describe the ways users combine and switch modes to meet goals:
Each pattern is assembled from combinations of the same four
[elemental] modes”
        <xref ref-type="bibr" rid="ref5">(Lamantia 2006)</xref>
        .
The five most frequent mode patterns are listed below. These have
been assigned descriptive (if somewhat informal) labels to aid
their characterisation, along with the sequence of modes they
represent and an associated example scenario:
      </p>
      <sec id="sec-5-1">
        <title>Comparison-driven optimization: (Analyze-Compare</title>
        <p>Evaluate) e.g. “Replace a problematic part with an
equivalent or better part without compromising quality
and cost”</p>
      </sec>
      <sec id="sec-5-2">
        <title>Exploration-driven optimization: (Explore-Analyze</title>
        <p>Evaluate) e.g. “Identify opportunities to optimize use of
tooling capacity for my commodity/parts”</p>
        <sec id="sec-5-2-1">
          <title>Strategic Insight (Analyze-Comprehend-Evaluate) e.g.</title>
          <p>“Understand a lead's underlying positions so that I can
assess the quality of the investment opportunity”</p>
        </sec>
        <sec id="sec-5-2-2">
          <title>Strategic Oversight (Monitor-Analyze-Evaluate) e.g.</title>
          <p>“Monitor &amp; assess commodity status against
strategy/plan/target”</p>
        </sec>
      </sec>
      <sec id="sec-5-3">
        <title>Comparison-driven Synthesis (Analyze-Compare</title>
        <p>Synthesize) e.g. “Analyze and understand
consumercustomer-market trends to inform brand strategy &amp;
communications plan”
Further insight may be derived by examining how the mode
patterns combine across all the scenarios to the form of a “mode
network”, as shown in Figure 1. Evidently, some modes act as
“terminal” nodes, i.e. entry points or exit points to a discovery
scenario. For example, Monitor and Explore feature only as entry
points at the initiation of a scenario, whilst Synthesize and
Evaluate feature only as exit points to a scenario.</p>
      </sec>
    </sec>
    <sec id="sec-6">
      <title>5. DESIGN PRINCIPLES FOR SEARCH</title>
    </sec>
    <sec id="sec-7">
      <title>AND DISCOVERY SOLUTIONS</title>
      <p>The modes establish a ‘taskonomy’ or collection of defined
discovery activities which are structurally consistent, domain and
scale independent, orthogonal, semantically distinct, conceptually
connected, and flexibly sequenceable. Such a profile -- analogous
to notes in the musical scale, or the words and phrases we
assemble into sentences -- should allow the modes to serve as a
language for the design of variable scale activity-centered
discovery solutions through common constructive mechanisms
such as concatenation, combination and nesting. And if the modes
do act as an elementary grammar for discovery, then sustained use
as a functional and interaction design language should result in
the creation of larger and more complex units of meaning which
offer cumulative value.</p>
      <p>Professional experience with employing the modes as both an
analytical framework for understanding discovery needs and as a
design grammar for the definition of discovery solutions suggests
that both implications are valid. Further, our observations of
using the modes suggest the existence of recognizable patterns in
the design of discovery solutions. We will briefly discuss some of
the patterns observed, doing so at three common levels of solution
scale: on the level of a single functional or interface element, for
whole screens or interfaces composed of multiple functional
elements, and for applications comprising multiple screens.</p>
    </sec>
    <sec id="sec-8">
      <title>5.1 Single element patterns</title>
      <p>5.1.1 Comparison Views
One of the most common design patterns is to support the need
for the Compare mode by creating A/B type comparison views
that present two display panes - each containing data display
charts or tables; or single items or groups of items - side by side to
emphasize similarities and differences.
5.1.2 Contextual Views
Another common design pattern supports the Analysis mode by
allowing a fore-grounded view of a single chart, table, item, or
list, accompanied by its contextual ‘halo’ - the full body of
information available about the element such as status, origin,
format, relationships to other elements; annotations; etc.</p>
    </sec>
    <sec id="sec-9">
      <title>5.2 Whole screen patterns</title>
      <p>5.2.1 Dashboard
One of the most common screen-level design patterns is to
support the Monitoring and Synthesis modes by presenting a
collection of metrics which in aggregate provide the status of
independent processes, groups, or progress versus goals in a
‘dashboard’ style screen.
5.2.2 Visual Discovery Screen: 4-Dimensions
A second common screen-level design pattern for discovery
experiences is the visual discovery screen, which supports modes
such Exploration, Evaluation, and Verification by layering views
that present visualizations of several dimensions of a single axis
of focus such as a core process, organizational unit, or KPI. When
switching between layered views, the axis in focus remains the
same, but the data and presentation in the dimensions adjusts to
match the preferred discovery mode.</p>
    </sec>
    <sec id="sec-10">
      <title>5.3 Application-level patterns</title>
      <p>5.3.1 Differentiated Application
The ‘Differentiated Application’ pattern assembles a collection of
individual screens whose distinct compositions and designs
support individual discovery modes of Analysis, Comparison,
Evaluation and Monitoring in aggregate to address the ‘Strategic
Oversight’ mode sequence. Application-level patterns often
address a spectrum of discovery needs for a group of users with
differing organizational responsibilities, such as management vs.
detailed analysis.</p>
    </sec>
    <sec id="sec-11">
      <title>6. DISCUSSION</title>
      <p>The above analysis is predicated on the notion that the user
scenarios provide a unique insight into the information needs of
enterprise knowledge workers. However, a number of caveats
apply to both the data and the approach.</p>
      <p>Firstly, the scenarios were originally generated to support the
development of a specific implementation rather than for the
analysis above. Therefore, the principles governing their creation
may not faithfully reflect the true distribution or priority of
information needs among the various end user populations.
Secondly, the particular sample we selected for this study was
based on a number of pragmatic factors (including availability),
which may not faithfully represent the true distribution or priority
among enterprise organizations. Thirdly, the data will inevitably
contain some degree of subjectivity, particularly in cases where
scenarios were generated by proxy rather than with direct end-user
contact. Fourthly, the data will inevitably contain some degree of
inconsistency in cases where scenarios were documented by
different individuals.</p>
      <p>
        We should also acknowledge a number of caveats concerning the
process itself. In inductive work with foundations in qualitatively
centered frameworks such as Grounded Theory, it is expected that
a number of iterations of a “propose-classify-refine” cycle will be
required for the process to converge on a stable output
        <xref ref-type="bibr" rid="ref11">(e.g. Rose
&amp; Levinson, 2004)</xref>
        . In addition, those iterations should involve a
variety of critical viewpoints, with the output tested and refined
using a separate, independent sample on each iteration. Likewise,
the process by which scenarios are classified would benefit from
further rigour: this is a critical part of the process and of course
relies on human judgement and inference, but that judgement
needs to go beyond simple word matching and be consistently
applied to each scenario so that subtle distinctions in meaning and
intent can be accurately identified and recorded.
      </p>
      <p>That said, some interesting comparisons can already be made with
the existing frameworks. For example, the first and third of the
search modes suggested by O’Day and Jeffries have also been
identified as distinct discovery modes in our own study, and the
second (arguably) maps on to one or more of the mode chains
identified above. Likewise, the search results analysis techniques
that O’Day &amp; Jeffries identified also present some interesting
parallels.</p>
    </sec>
    <sec id="sec-12">
      <title>7. CONCLUSIONS AND FUTURE</title>
    </sec>
    <sec id="sec-13">
      <title>DIRECTIONS</title>
      <p>To design better search and discovery experiences we must
understand the complexities of the human-information seeking
process. In this paper, we have examined the needs and
behaviours of varied individuals across a range of search and
discovery scenarios within various types of enterprise. In so
doing, we have extended the classic IR concept of
informationseeking to a broader notion of discovery-oriented problem
solving, accommodating the much wider range of behaviours
required to fulfil the typical goals and objectives of enterprise
knowledge workers.</p>
      <p>In addition, we have proposed an alternative model focused on
information discovery rather than information seeking which has
at its core a taxonomy of “modes of discovery” that knowledge
workers employ to satisfy their information search and discovery
goals. We have also examined some of the initial implications of
this model for the design of more effective search and discovery
platforms and tools.</p>
      <p>Suggestions for future work include further iterations on the
“propose-classify-refine” cycle using independent data. This data
should ideally be acquired based on a principled sampling strategy
that attempts where possible to address any biases introduced in
the creation of the original scenarios. In addition, this process
should be complemented by empirical research and observation of
knowledge workers in context to validate and refine the discovery
modes and triggers that give rise to the observed patterns of usage.</p>
    </sec>
  </body>
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